Spring tweezers



Jan. 23, 1923. 1,443,086

w. M. mucHow. SPRING Twgzzens. FILED SEPT 27, 1920.

Patented Jan. 23, 1923.

WILLIAM MARK MUCI-IOVJ', OF EVANSTON, ILLINOIS.

SPRING TWEEZER-S.

Application filed September 27, 1920. Serial No. 413,197.

To all whom it may concern.

Be it known that I, W'ILLIAM linen MU- oHow. a citizen oi? the United States. and resident of Evanston, in the county of Cook and Stateoi Illinois, have invented certain new and useful Improvements in Spring Tweezers, of which the following is specification.

My invention relates to gripping or holding devices and particularly to a novel device adapted for use dentists and others who utilize delicate tweezers. I

One of the objects of my invention is to provide means for firmly and yet delicately holding small objects in a relatively permanent manner. particular reference being had to a device adapted for holding crowns or other dental manufactures during the process of forming and soldering the same. In shaping and fitting crowns and other tooth repairs it is customary to heat the same by placin the article in question in a flame for a short period of time and this is usually accomplished by holding the part in question in a pair of tweezers oi common form. 'This is objectionable "for the reason that the pressure exerted on the part being heated is likely to be irregular and, at times, great enough to crush or distort the part particularly after it has been heated and is soft. The parts in question are, particularly when heated, very fragile and easily bent and it is diflicult, if not impossible, to securely grip them while in this condition without causing some distortion. In the device here disclosed I provide means for gripping and holding fragile parts with any degree of firmness, with the assurance that the intensity of this grip will not be changed to the extent of decreasing or diminishing it until such change is desired.

The result is secured by providin a tubu lar element within which a pair of spring fingers are mounted for lon itudinal sliding engagement. These spring fingers are joined by a loop having inherent resiliency which tends to spread the fingers. At the opposite ends the fingers are bent outwardly to such an extent that as the fingers are withdrawn into the tube the extremities are brought together. It will be seen that the degree of force with which an article is gripped may be regulated to a nlcety and that, when once regulated, there will be no change until desired by the user. This result is assured by the fact that as the spring fingers have a position is in the tendency to spring apart around the loop as a center, they will assume a curved form when confined within the tube, and the arcu ate eatremities alone will contact the walls ol the tube. This contact provides sufficient frictional 1' sistance to hold the parts in adjusted position. The resiliency which is relied upon to hold the lingers in the desired portions of the spring member which is removed from the extremities which become heated when the device is in service. Thus the temper will not be re moved from the spring.

Another advantage in the construction proposed is that the length of the projecting ends of the tweezers may be varied. as desired, by slightly distorting the loop. This adapts the device for certain classes of work in which it is required that one extremity of the tweezers project beyond the opposite end. I

nether object is to so crr struct the tubular member as to provide eyes at the ends, the result being secured by splitting the tube and bending back the split ends on each side.

The invention will be more readily understood by reference to the accompanying drawing, in which,

Fig] l is a. longitudinal sectional view through a device constructed in accordance with my invention;

Fig. 2 is an elevation showing the position which thespring fingers tend to assume it not restrained by the tube;

Fig. 3 is a similar view showing an adaptation of the fingers in which one end projects boyon d the other? and i Fig. l is a sectional ie on the line of Fig. 1.

In the drawings it v vide a tube 10 havin pair- 0 e grips 11. 12 at one end; these being formed by splitting the tube and ,hen ben ling baclr the split portions and joining the same by soldering or otherwise to the tube at the points 13. This enables the provision of finger grips which are a necessary or at least desirable adjunct to a device of this sort. Mounted within the tube is a spring element composed of normally straight portions 14, a loop 15 and tweezer portions 16. This element may be formed by bending a flat light-weight spring until it has a permanent shape substantially the same as that shown in dotted lines in Fig. 2. When this is compressed and forced within the tube it will be seen that there will be a tendency to expand and the straight portions 14 will as sumo a curved position, as shown in Fig. 1. In this position the fingers contact with the tube at substantially one point. The frictional resistance is, however, suflicient to retain the spring element in any adjusted position. The tweezer ends of the device are formed by first bending the end portions outwardly and thence inwardly into line. The outward bend, as shown in Fig. 2, is greater than the diameter of the tube and as the fingers are withdrawn by grasping the loop the extremities of the fingers are brought together. I In this manner it will be seen that a device may be gripped with any desired degree of firmness and that this grip will remain constant until changed.

In the illustration of Fig. 3 it will be seen that the length of the fingers maybe changed, as desired, by slightly distorting the loop member. This will be found desirable under certain circumstances.

It will be understood that the size of the spring element relative to the diameter of the tube will be gauged in such manner that the springs cannot move past each other, but will be retained in gripping relation.

Obviously also modifications may be made in the construction shown and I do not wish to be limited other than as indicated in the appended claims.

I claim:

1. In tweezers, the combination of a tube and spring fingers mounted within the tube with capacity for longitudinal sliding movement, said fingers being joined by a yoke projecting outside of one extremity of the tube, the opposite end of the fingers being shaped to permit the extremities to be brought into contact,- the resiliency of the fingers being such that said fingers contact the interior of the tube at a point removed from the end of the tube, substantially as described.

2. Spring tweezers comprising in combination, a tubular member and a spring doubled upon itself to provide a loop adapted to project beyond one end of the tube, and a pair of tweezers adapted to project beyond the opposite end of the tube, the tweezer ends being moved toward and form each other by moving the spring member longitudinally of the tube, the spring memher being so bent as to have inherent resiliency in its loop end and to tend to expand the fingers whereby the fingers are oppositely curved within the tube and tend to bear at one point against the tube at a point removed from the tweezer end thereof, substantially as described.

3. Ina device of the class described, the combination of a tubular member,.and spring fingers mounted and adapted for longitudinal movement within said tubular member in order to grip or hold an object in the projecting ends of the fingers, said tube being provided with eyes or finger grips at one end, each of said eyes being formed from a portion of said tube which is bent back upon itself, substantially as described.

Signedat Chicago, Illinois, .this 24th day of September, 1920.

WILLIAM MARK MUCHOW. 

